The hormone angiotensin II is recognized as one of the most potent vasopressor agents that produces hypertension in mammals. The action of the enzyme renin on the plasma protein substrate angiotensinogen results in the production of an inactive decapeptide, angiotensin I, which upon conversion by the nonselective selective angiotensin converting enzyme (ACE) provides angiotensin II, the active hormone. See, e.g., Regoli et al., Pharm. Rev., 26, 69 (1974).
Angiotensin II causes vasoconstriction and stimulates aldosterone secretion (from the adrenal gland) that results in a rise of both blood volume and pressure. Inhibitors of angiotensin II are therefore useful in treating hypertension, congestive heart failure, renal insufficiency associated with diabetic or hypertensive nephropathy, and glaucoma. See Garrison et al., in The Pharmacological Basis of Therapeutics, 8th Edition, Eds. A. G. Gilman, E. S. Goodman, T. W. Rall, A. S. Nies, and P. Taylor, Pergamon Press, New York, 1990: p. 761-762; and Dzau V. J., The New Eng. J. Med. 324: 1124-1130 (1991).
Angiotensin II also can act on other organs such as the brain (Fitzsimmons, Rev. Physiol. Biochem. Pharmacol., 87, 117, (1980)). Antagonists of angiotensin II are therefore useful in enhancing cognitive performance in patients affected by conditions such as age associated mental impairment or Alzheimer's disease and in treating cognitive disorders such as anxiety. See Dennes et al. Brit. J. Pharmacol. 105: 88p (Apr. 1992); and Barnes, J. M., et al. FASEB J. 5: 678 (Mar. 1991).
In addition, angiotensin II acts on a variety of glandular tissues including the kidney, liver, and ovaries. Antagonists of angiotensin II are useful in treating conditions, disorders, or diseases of these tissues associated with excessive or unregulated angiotensin II activity. Antagonists of angiotensin II are also useful in treating kidney damage due to nonsteroidal antiinflammatory agents.
Angiotensin II has a role in regulation of the rate of cell growth and differentiation. Inhibitors of angiotensin II are therefore useful in treating disorders marked by excessive cell proliferation such as restenosis. See, e.g., Naftilan et al., J. Clin. Invest, 83, 1419 (1989), Kauffman et al., Life Sciences, 49: 223-228 (1991), and Jackson et al., Nature, 335, 437 (1988).
Some antihypertensive agents act as inhibitors of ACE thus blocking the formation of angiotensin II and its resulting increase of blood pressure. More recently, both peptide and nonpeptide receptor antagonists of angiotensin II have been disclosed--see, e.g., EPO Patent Application Publication 253310 and references contained therein, and Chiu et al., J. Pharmacol. Exp. Ther., 250, 867 (1989). Although these compounds and others have had an important role in uncovering the physiological roles for Angiotensin II, their therapeutic usefulness was ultimately limited by either partial agonist activity, metabolic instability or both. See Ashworth R. W. Birkhauser Verlag 26 (1982).
The present invention provides novel, potent, and effective compounds that antagonize angiotensin II at receptor sites in the body and are therefore useful in treating conditions associated with excessive or unregulated angiotensin II activity such as hypertension, congestive heart failure, cognitive disorders, renal insufficiency associated with diabetic or hypertensive nephropathy, glaucoma, kidney damage due to nonsteroidal antiinflammatory agents, and restenosis.